Cornell sounds nanoparticle health warning

One of the latest Great New Thing crazes to sweep the technology world is nanotech, the use of infinitesimally small particles to create everything from medicines, laundry detergent additives, dental fillings, and food wrappings to “smart dust” to track inventories and spies [partial lists of applications are here and here].

Nanoparticles are incredibly small, ranging in size from 1 to 100 nanometers, with a nanometer being one billionth of a meter. The things are so small, they’re invisible to even the most powerful optical microscopes.

One of the major centers of nanotechnology research is Lawrence Berkeley National Laboratory [LBNL], the Department of Energy research facility run by UC Berkeley.

Current head of LBNL is Paul Alvisatos, who replaced Steve Chu after he was tapped by Barack Obama to serve as Secretary of Energy. One of Alvisatos’s specialties is nanotech, and he played the lead role in the creation of the lab’s Molecular Foundry, where nanotechnology research is conducted on a hillside located high above the city in a major earthquake zone.

We can also expect that nanotech will be employed in LBNL’s planned billion-dollar-plus second campus on the nearby Richmond shoreline.

Oh, and as for the smart dust concept, the whole notion was created by the Defense Department, and UC Berkeley scientists are currently working on projects that includes such applications as “battlefield surveillance, treaty monitoring, transportation monitoring, scud hunting.” CNN headlined a story on the technology this way: ‘Smart dust’ aims to monitor everything.

We’ll have more on Berkeley after the jump.

The introduction of any new technology provokes anxieties, but when it’s both invisible and pervasive, the anxiety increases. Some of it is clearly exaggerated, and you might call it neophobia, the fear of the new. But there’s every reason for caution, and research is beginning to shot that some of that concern is very well founded.

Billions of engineered nanoparticles in foods and pharmaceuticals are ingested by humans daily, and new Cornell research warns they may be more harmful to health than previously thought.

A research collaboration led by Michael Shuler, the Samuel B. Eckert Professor of Chemical Engineering and the James and Marsha McCormick Chair of Biomedical Engineering, studied how large doses of polystyrene nanoparticles — a common, FDA-approved material found in substances from food additives to vitamins — affected how well chickens absorbed iron, an essential nutrient, into their cells.

The results were reported online Feb. 12 in the journal Nature Nanotechnology.

The researchers tested both acute and chronic nanoparticle exposure using human gut cells in petri dishes as well as live chickens and reported matching results. They chose chickens because these animals absorb iron into their bodies similarly to humans, and they are also similarly sensitive to micronutrient deficiencies, explained Gretchen Mahler, Ph.D. ’08, the paper’s first author and former Cornell graduate student and postdoctoral associate.

The researchers used commercially available, 50-nanometer polystyrene carboxylated particles that are generally considered safe for human consumption. They found that following acute exposure, a few minutes to a few hours after consumption, both the absorption of iron in the in vitro cells and the chickens decreased.

But following exposure of 2 milligrams per kilogram for two weeks — a slower, more chronic intake — the structure of the intestinal villi began to change and increase in surface area. This was an effective physiological remodeling that led to increased iron absorption.

“This was a physiological response that was unexpected,” Mahler said.

Shuler noted that in some sense this intestinal villi remodeling was positive because it shows the body adapts to challenges. But it serves to underscore how such particles, which have been widely studied and considered safe, cause barely detectable changes that could lead to, for example, over-absorption of other, harmful compounds.

Human exposure to nanoparticles is only increasing, Shuler continued.

“Nanoparticles are entering our environment in many different ways,” Shuler said. “We have some assurance that at a gross level they are not harmful, but there may be more subtle effects that we need to worry about.”

The paper included Cornell co-authors Mandy Esch, a research associate in biomedical engineering; Elad Tako, a research associate at the Robert W. Holley Center for Agriculture and Health; Teresa Southard, assistant professor of biomedical sciences; Shivaun Archer, senior lecturer in biomedical engineering; and Raymond Glahn, senior scientist with the USDA Agricultural Research Service and courtesy associate professor in the Department of Food Science. The work was supported by the National Science Foundation; New York State Office of Science, Technology and Academic Research; Army Corp of Engineers; and U.S. Department of Agriculture.

Another study hints at dangers

Last May, nanotechwire reported on another story suggesting that nanoparticles have a dark side:

Researchers from the University of Iowa Roy J. and Lucille A. Carver College of Medicine have found that inhaled carbon black nanoparticles create a double source of inflammation in the lungs.

Their findings were published online in the April 27 edition of the Journal of Biological Chemistry. Martha Monick, Ph.D., UI professor of internal medicine, was lead author of the paper, “Induction of Inflammasome Dependent Pyroptosis by Carbon Black Nanoparticles,” which outlined the results.

Monick said researchers expected to find one level of inflammation when cells were exposed to carbon black nanoparticles. They were surprised, however, to find that nanoparticles activated a special inflammatory process and killed cells in a way that further increased inflammation. She said the research showed that the intake of carbon black nanoparticles from sources such as diesel fuel or printer ink caused an initial inflammatory response in lung cells. The surprising results came when the team discovered that these nanoparticles killed macrophages — immune cells in the lungs responsible for cleaning up and attacking infections — in a way that also increases inflammation.

“Apoptosis is one way cells die in which all the contents stay in the cell, the cell just keeps shrinking onto itself and the surrounding tissue is protected,” Monick said. “We thought that was what was happening with the carbon nanoparticles; we were wrong. A different process called pyroptosis was occurring, causing the cells to burst and spill their contents.”

The issue of nanotechnology arose here in Berkeley with the launch of the Molecular Foundry.

Local activists had pushed the city to adopt the Precautionary Principle, which basically says that it’s important to thoroughly question the implications of significant changes in the environment.

The city also passed an ordinance specifically focused on nanotech, the Manufactured Nanoparticle Disclosure Ordinance, passed in December 2006.

But when deadline time for the first reports under the new law, LBNL didn’t file. Judith Scherr reported on the reasons in a 5 June 2007 article in the Berkeley Daily Planet:

The lab’s response was written by Howard K. Hatayama, of LBNL’s Environment, Health and Safety Division. Hatayama did not return a call for comment from the Daily Planet.

Writing the city on May 31, Hatayama said the wide range of nano materials render the characterization of toxicity of each “extremely challenging.” However, without going into detail, he underscored that the lab follows safety procedures: “LBNL has procedures that take into account the toxicity, process and controls during evaluation of the work performed, in consultation with health and safety specialists as necessary.”

The university response noted its independence from city regulation. “The university, as a state entity, is exempt from the city of Berkeley’s manufactured nanoscale material disclosure ordinance,” says a May 31 letter written by Mark Freiberg, UC Berkeley’s hazardous materials manager. Freiberg was out of town and unavailable for comment. His letter to the city was forwarded by the university’s Public Information Office.

Nanoparticles became an issue again in 2007, when LBNL’s Long Range Development Plan was up for approval by the University of California Board of Regents. The report included this section [PDF], added after an earlier hearing:

The City of Berkeley in 2006 approved a change to the Hazardous Materials and Wastes Management portion of its Municipal Code. The amendment adds to facilities subject to reporting requirements, in addition to facilities that handle hazardous material or waste in certain quantities, those facilities “that manufacture or use manufactured nanoparticles,” and requires such facilities to disclose “current toxicology of the materials reported, to the extent known, and how the facility will safely handle, monitor, contain, dispose, track inventory, prevent releases and mitigate such materials.”

During the final public hearing on the plan’s Environmental Impact Report a month later, nanotechbology surfaced again as we reported for the Berkeley Daily Planet 13 July:

As for the city’s plea for the lab to adopt the precautionary principle, the DEIR states following existing laws and regulations are adequate mitigations.

Declaring the lab isn’t covered by the city’s Manufactured Nanoparticle Disclosure Ordinance, which requires reports on facilities making or using the microscopic technology, the lab “intends to provide on-going information of interest to the City in regard to the Lab’s work” in the nano realm.

While acknowledging new programs will lead to significant increases in the amounts of dangerous materials stored and created on site, the lab contends existing rules and laws cover the dangers.

Response to concerns over nanotech in a letter from Pamela Shivola, the EIR replied that the lab has safely worked with nano-sized bacteria and viruses.

Responding to her concerns about the BP-funded Energy Biosciences Institute, which will be included in the Helios Building described in the EIR, the document states that a separate, full environmental review will be prepared for that building. The structure will also be built so that it won’t disturb an existing underground plume of tritium in the area, according to the LRDP EIR.

We also note that nanotechology research is also being to be conducted in downtown Berkeley in in the labs of the Helios Building, erected at state expense to house the labs of the Energy Biosciences Institute, the $500 million project funded by BP [formerly British Petroleum, and before that the Anglo Iranian Oil Company] as part of their efforts to develop new energy sources. Currently nanotechnology is being used elsewhere in both agrofuel processing, the major focus of the EBI, and solar panel technology, another BP focus.

We’ll close on another excerpt from Sherr’s article:

Making sure that there is training in safety procedures in handling the nanoparticles is an important aspect of the reporting, [City of Berkeley Toxics Manager Nabil] Al-Hadithy said. The university’s letter says training “may be provided as part of the training provided on the laboratory’s Chemical Hygiene Plan.”

Al-Hadithy noted that state and federal standards for disposal of the particles have not been developed. “They can be dumped in a sink or in a garbage can,” he said, noting that he had hoped that LBNL’s response would have helped in the development of such standards.